Nature vs nurture seems to play a role in every aspect of our lives and that is true even for physical abilities associated with sports!

Each week on TestTubePlus, we pick one topic and cover it from multiple angles. This week's subject is health and fitness. Why is it so hard to stay fit? What motivates some of us? How much does genetics play a part in athletic ability? Is there a limit to human's abilities? In the first episode, Trace talked about some of the reasons why our brain hates exercise. For the last two episodes, Trace was joined by guest host Amy Shira Teitel to discuss exercise supplements and how working out can help you have better sex. Today, Trace tries to answer the question: are elite athletes born or can anyone train to be an olympian?

There are lots of studies on how relevant genetics are to a person's athletic ability. Genes can affect a persons aerobic capacity, response to training, anaerobic performance, muscle strength and power, neuromuscular coordination, bone density muscle fiber type distributions, and many more components. Dan Agin, Associate Professor of Molecular Genetics and Cell Biology at the University of Chicago has studied the role of fetal programming (also known as prenatal programming), in development of athletes. He's quoted for saying the following: "General idea that during development of the embryo and fetus important physiological parameters can be reset by environmental events--and of most importance--the resetting can endure into adulthood and even affect the following generation to produce a trans-generational non-genetic disorder."

Basically, fetal programming has well-documented effects on risks of many diseases, and recent evidence shows fetal programming affects human athletic performance as well. According to studies, things like low birth weight can predict low fat-free mass or lean body mass later in life. Lean body mass is the amount of weight your body is carrying that isn't fat. So, your fetal environment can affect how much muscle you might be able to carry. But this is just someone's genetic predisposition; it doesn't mean that fetal environment will guarantee how fit that person will be when the grow up. Like so many other things, a person's athletic ability is a combination of nature and nurture. Trace explains some how some of these nuances come into play.

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Can Genes Predict Athletic Ability? (Scientific American) "What if sideline rage could be nipped in the bud with a quick genetic test that told Mom and Dad what sports - if any - Junior could master??

Effect of Goal Setting on Motivation and Adherence in a Six-Week Exercise Program (Academia) "The aim of the study was to utilize a goal-setting intervention to examine the impact on motivation and adherence during a six-week exercise program."

Exercise Motivation: What Starts and Keeps People Exercising? (University of New Mexico) "Although extolling all the benefits of exercise seems impressive, it is apparent that this approach by itself does not assure consistent exercise compliance for most individuals. Regular exercise is a complex, multi-factorial behavior that exercise professionals and scientists need to better understand, in order to help clients stay active and healthy."